I have the Orca also. I have been running it for 5 months now. I haven't had much issue with it. I removed all the internal media apart from the sponge which I will be cutting down as i am going through a nitrate spike at the moment. I put a bag of Phosphate removal stuff in the left chamber. I have been running it without using the built in skimmer because of all the issues you have probably read already, I do about 15-20% waterchange a week, which is easy with this small volume of water. I have added a Korella Nano pump to increase the flow. Reading the threads on this site I will purchase a replacement skimmer.
Overall I like the Orca, the hood is tidy. good arrangement to feed cables and hoses out of the tank. I haven't had the issues with the fan noise yet, as soon as I do I will buy some Silent PC fans.
Doing it again I would probably go for something with a larger footprint.